Commit Graph

3157 Commits

Author SHA1 Message Date
Tom Zanussi
52a7f16ded tracing: Add support for multiple hist triggers per event
Allow users to define any number of hist triggers per trace event.
Any number of hist triggers may be added for a given event, which may
differ by key, value, or filter.

Reading the event's 'hist' file will display the output of all the
hist triggers defined on an event concatenated in the order they were
defined.

Link: http://lkml.kernel.org/r/48a0c8dd34c344571de880fb35e211c6d9a28961.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 18:55:59 -04:00
Tom Zanussi
d0bad49bb0 tracing: Add enable_hist/disable_hist triggers
Similar to enable_event/disable_event triggers, these triggers enable
and disable the aggregation of events into maps rather than enabling
and disabling their writing into the trace buffer.

They can be used to automatically start and stop hist triggers based
on a matching filter condition.

If there's a paused hist trigger on system:event, the following would
start it when the filter condition was hit:

  # echo enable_hist:system:event [ if filter] > event/trigger

And the following would disable a running system:event hist trigger:

  # echo disable_hist:system:event [ if filter] > event/trigger

See Documentation/trace/events.txt for real examples.

Link: http://lkml.kernel.org/r/f812f086e52c8b7c8ad5443487375e03c96a601f.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 18:55:57 -04:00
Tom Zanussi
6a475cb17f tracing: Remove restriction on string position in hist trigger keys
If we assume the maximum size for a string field, we don't have to
worry about its position.  Since we only allow two keys in a compound
key and having more than one string key in a given compound key
doesn't make much sense anyway, trading a bit of extra space instead
of introducing an arbitrary restriction makes more sense.

We also need to use the event field size for static strings when
copying the contents, otherwise we get random garbage in the key.

Also, cast string return values to avoid warnings on 32-bit compiles.

Finally, rearrange the code without changing any functionality by
moving the compound key updating code into a separate function.

Link: http://lkml.kernel.org/r/8976e1ab04b66bc2700ad1ed0768a2de85ac1983.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 18:55:56 -04:00
Namhyung Kim
79e577cbce tracing: Support string type key properly
The string in a trace event is usually recorded as dynamic array which
is variable length.  But current hist code only support fixed length
array so it cannot support most strings.

This patch fixes it by checking filter_type of the field and get
proper pointer with it.  With this, it can get a histogram of exec()
based on filenames like below:

  # cd /sys/kernel/tracing/events/sched/sched_process_exec
  # cat 'hist:key=filename' > trigger
  # ps
   PID TTY       TIME CMD
     1 ?     00:00:00 init
    29 ?     00:00:00 sh
    38 ?     00:00:00 ps
  # ls
  enable  filter  format  hist  id  trigger
  # cat hist
  # trigger info: hist:keys=filename:vals=hitcount:sort=hitcount:size=2048 [active]

  { filename: /usr/bin/ps                         } hitcount:          1
  { filename: /usr/bin/ls                         } hitcount:          1
  { filename: /usr/bin/cat                        } hitcount:          1

  Totals:
      Hits: 3
      Entries: 3
      Dropped: 0

Link: http://lkml.kernel.org/r/610180d6df0cfdf11ee205452f3b241dea657233.1457029949.git.tom.zanussi@linux.intel.com

Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
[ Added (unsigned long) typecast to fix compile warning ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 18:55:00 -04:00
Tom Zanussi
69a0200c2e tracing: Add hist trigger support for stacktraces as keys
It's often useful to be able to use a stacktrace as a hash key, for
keeping a count of the number of times a particular call path resulted
in a trace event, for instance.  Add a special key named 'stacktrace'
which can be used as key in a 'keys=' param for this purpose:

    # echo hist:keys=stacktrace ... \
               [ if filter] > event/trigger

Link: http://lkml.kernel.org/r/87515e90b3785232a874a12156174635a348edb1.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:19:01 -04:00
Tom Zanussi
316961988b tracing: Add hist trigger 'syscall' modifier
Allow users to have syscall id fields displayed as syscall names in
the output by appending '.syscall' to field names:

   # echo hist:keys=aaa.syscall ... \
              [ if filter] > event/trigger

Link: http://lkml.kernel.org/r/2bab1e59933d76a14b545bd2e02f80b8b08ac4d3.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:18:04 -04:00
Tom Zanussi
6b4827ad02 tracing: Add hist trigger 'execname' modifier
Allow users to have common_pid field values displayed as program names
in the output by appending '.execname' to a common_pid field name:

   # echo hist:keys=common_pid.execname ... \
              [ if filter] > event/trigger

Link: http://lkml.kernel.org/r/e172e81f10f5b8d1f08450e3763c850f39fbf698.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:17:56 -04:00
Tom Zanussi
c6afad49d1 tracing: Add hist trigger 'sym' and 'sym-offset' modifiers
Allow users to have address fields displayed as symbols in the output
by appending '.sym' or 'sym-offset' to field names:

   # echo hist:keys=aaa.sym,bbb.sym-offset ... \
              [ if filter] > event/trigger

Link: http://lkml.kernel.org/r/87d4935821491c0275513f0fbfb9bab8d3d3f079.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:17:51 -04:00
Tom Zanussi
0c4a6b4666 tracing: Add hist trigger 'hex' modifier for displaying numeric fields
Allow users to have numeric fields displayed as hex values in the
output by appending '.hex' to field names:

   # echo hist:keys=aaa,bbb.hex:vals=ccc.hex ... \
              [ if filter] > event/trigger

Link: http://lkml.kernel.org/r/67bd431edda2af5798d7694818f7e8d71b6b3463.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:17:43 -04:00
Tom Zanussi
e86ae9baac tracing: Add hist trigger support for clearing a trace
Allow users to append 'clear' to an existing trigger in order to have
the hash table cleared.

This expands the hist trigger syntax from this:
    # echo hist:keys=xxx:vals=yyy:sort=zzz.descending:pause/cont \
           [ if filter] >> event/trigger

to this:

    # echo hist:keys=xxx:vals=yyy:sort=zzz.descending:pause/cont/clear \
          [ if filter] >> event/trigger

Link: http://lkml.kernel.org/r/ae15dd0d9b2f7af07a37c1ff682063e2dbcdf160.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:17:35 -04:00
Tom Zanussi
83e99914c9 tracing: Add hist trigger support for pausing and continuing a trace
Allow users to append 'pause' or 'continue' to an existing trigger in
order to have it paused or to have a paused trace continue.

This expands the hist trigger syntax from this:
    # echo hist:keys=xxx:vals=yyy:sort=zzz.descending \
          [ if filter] >> event/trigger

to this:

    # echo hist:keys=xxx:vals=yyy:sort=zzz.descending:pause or cont \
          [ if filter] >> event/trigger

Link: http://lkml.kernel.org/r/b672a92c14702cb924cdf6fc27ea1809bed04907.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:17:29 -04:00
Tom Zanussi
e62347d245 tracing: Add hist trigger support for user-defined sorting ('sort=' param)
Allow users to specify keys and/or values to sort on.  With this
addition, keys and values specified using the 'keys=' and 'vals='
keywords can be used to sort the hist trigger output via a new 'sort='
keyword.  If multiple sort keys are specified, the output will be
sorted using the second key as a secondary sort key, etc.  The default
sort order is ascending; if the user wants a different sort order,
'.descending' can be appended to the specific sort key.  Before this
addition, output was always sorted by 'hitcount' in ascending order.

This expands the hist trigger syntax from this:

    # echo hist:keys=xxx:vals=yyy \
          [ if filter] > event/trigger

to this:

    # echo hist:keys=xxx:vals=yyy:sort=zzz.descending \
          [ if filter] > event/trigger

Link: http://lkml.kernel.org/r/b30a41db66ba486979c4f987aff5fab500ea53b3.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:17:19 -04:00
Tom Zanussi
76a3b0c8ac tracing: Add hist trigger support for compound keys
Allow users to specify multiple trace event fields to use in keys by
allowing multiple fields in the 'keys=' keyword.  With this addition,
any unique combination of any of the fields named in the 'keys'
keyword will result in a new entry being added to the hash table.

Link: http://lkml.kernel.org/r/0cfa24e6ac3b0dcece7737d94aa1f322ae3afc4b.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:16:33 -04:00
Tom Zanussi
f2606835d7 tracing: Add hist trigger support for multiple values ('vals=' param)
Allow users to specify trace event fields to use in aggregated sums
via a new 'vals=' keyword.  Before this addition, the only aggregated
sum supported was the implied value 'hitcount'.  With this addition,
'hitcount' is also supported as an explicit value field, as is any
numeric trace event field.

This expands the hist trigger syntax from this:

  # echo hist:keys=xxx [ if filter] > event/trigger

to this:

  # echo hist:keys=xxx:vals=yyy [ if filter] > event/trigger

Link: http://lkml.kernel.org/r/2a5d1adb5ba6c65d7bb2148e379f2fed47f29a68.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:16:23 -04:00
Tom Zanussi
7ef224d1d0 tracing: Add 'hist' event trigger command
'hist' triggers allow users to continually aggregate trace events,
which can then be viewed afterwards by simply reading a 'hist' file
containing the aggregation in a human-readable format.

The basic idea is very simple and boils down to a mechanism whereby
trace events, rather than being exhaustively dumped in raw form and
viewed directly, are automatically 'compressed' into meaningful tables
completely defined by the user.

This is done strictly via single-line command-line commands and
without the aid of any kind of programming language or interpreter.

A surprising number of typical use cases can be accomplished by users
via this simple mechanism.  In fact, a large number of the tasks that
users typically do using the more complicated script-based tracing
tools, at least during the initial stages of an investigation, can be
accomplished by simply specifying a set of keys and values to be used
in the creation of a hash table.

The Linux kernel trace event subsystem happens to provide an extensive
list of keys and values ready-made for such a purpose in the form of
the event format files associated with each trace event.  By simply
consulting the format file for field names of interest and by plugging
them into the hist trigger command, users can create an endless number
of useful aggregations to help with investigating various properties
of the system.  See Documentation/trace/events.txt for examples.

hist triggers are implemented on top of the existing event trigger
infrastructure, and as such are consistent with the existing triggers
from a user's perspective as well.

The basic syntax follows the existing trigger syntax.  Users start an
aggregation by writing a 'hist' trigger to the event of interest's
trigger file:

  # echo hist:keys=xxx [ if filter] > event/trigger

Once a hist trigger has been set up, by default it continually
aggregates every matching event into a hash table using the event key
and a value field named 'hitcount'.

To view the aggregation at any point in time, simply read the 'hist'
file in the same directory as the 'trigger' file:

  # cat event/hist

The detailed syntax provides additional options for user control, and
is described exhaustively in Documentation/trace/events.txt and in the
virtual tracing/README file in the tracing subsystem.

Link: http://lkml.kernel.org/r/72d263b5e1853fe9c314953b65833c3aa75479f2.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:16:14 -04:00
Tom Zanussi
3b772b96b8 tracing: Update some tracing_map constants and comments
Make it clear exactly how many keys and values are supported through
better defines, and add 1 to the vals count, since normally clients
want support for at least a hitcount and two other values.

Also, note the error return value for tracing_map_add_key/val_field()
in the comments.

Link: http://lkml.kernel.org/r/6696fa02ebc716aa344c27a571a2afaa25e5b4d4.1457029949.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:16:06 -04:00
Steven Rostedt (Red Hat)
8d44f2f34f tracing: Fix TRACING_MAP Kconfig
The config option for TRACING_MAP has "default n", which is not needed
because the default of configs is 'n'.

Also, since the TRACING_MAP has no config prompt, there's no reason to
include "If in doubt, say N" in the help text.

Fixed a typo in the comments of tracing_map.h.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:15:54 -04:00
Tom Zanussi
08d43a5fa0 tracing: Add lock-free tracing_map
Add tracing_map, a special-purpose lock-free map for tracing.

tracing_map is designed to aggregate or 'sum' one or more values
associated with a specific object of type tracing_map_elt, which
is associated by the map to a given key.

It provides various hooks allowing per-tracer customization and is
separated out into a separate file in order to allow it to be shared
between multiple tracers, but isn't meant to be generally used outside
of that context.

The tracing_map implementation was inspired by lock-free map
algorithms originated by Dr. Cliff Click:

 http://www.azulsystems.com/blog/cliff/2007-03-26-non-blocking-hashtable
 http://www.azulsystems.com/events/javaone_2007/2007_LockFreeHash.pdf

Link: http://lkml.kernel.org/r/b43d68d1add33582a396f553c8ef705a33a6a748.1449767187.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 12:04:59 -04:00
Steven Rostedt
c37775d578 tracing: Add infrastructure to allow set_event_pid to follow children
Add the infrastructure needed to have the PIDs in set_event_pid to
automatically add PIDs of the children of the tasks that have their PIDs in
set_event_pid. This will also remove PIDs from set_event_pid when a task
exits

This is implemented by adding hooks into the fork and exit tracepoints. On
fork, the PIDs are added to the list, and on exit, they are removed.

Add a new option called event_fork that when set, PIDs in set_event_pid will
automatically get their children PIDs added when they fork, as well as any
task that exits will have its PID removed from set_event_pid.

This works for instances as well.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 10:28:28 -04:00
Steven Rostedt
f4d34a87e9 tracing: Use pid bitmap instead of a pid array for set_event_pid
In order to add the ability to let tasks that are filtered by the events
have their children also be traced on fork (and then not traced on exit),
convert the array into a pid bitmask. Most of the time the number of pids is
only 32768 pids or a 4k bitmask, which is the same size as the default list
currently is, and that list could grow if more pids are listed.

This also greatly simplifies the code.

Suggested-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 10:28:27 -04:00
Steven Rostedt
9ebc57cfaa tracing: Rename check_ignore_pid() to ignore_this_task()
The name "check_ignore_pid" is confusing in trying to figure out if the pid
should be ignored or not. Rename it to "ignore_this_task" which is pretty
straight forward, as a task (not a pid) is passed in, and should if true
should be ignored.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 10:28:26 -04:00
Arnd Bergmann
266a0a790f bpf: avoid warning for wrong pointer cast
Two new functions in bpf contain a cast from a 'u64' to a
pointer. This works on 64-bit architectures but causes a warning
on all 32-bit architectures:

kernel/trace/bpf_trace.c: In function 'bpf_perf_event_output_tp':
kernel/trace/bpf_trace.c:350:13: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
  u64 ctx = *(long *)r1;

This changes the cast to first convert the u64 argument into a uintptr_t,
which is guaranteed to be the same size as a pointer.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 9940d67c93 ("bpf: support bpf_get_stackid() and bpf_perf_event_output() in tracepoint programs")
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-18 20:58:55 -04:00
Michael Ellerman
8404410b29 Merge branch 'topic/livepatch' into next
Merge the support for live patching on ppc64le using mprofile-kernel.
This branch has also been merged into the livepatching tree for v4.7.
2016-04-18 20:45:32 +10:00
Jiri Kosina
4d4fb97a62 Merge branch 'topic/livepatch' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux into for-4.7/livepatching-ppc64le
Pull livepatching support for ppc64 architecture from Michael Ellerman.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2016-04-15 11:42:51 +02:00
Daniel Borkmann
074f528eed bpf: convert relevant helper args to ARG_PTR_TO_RAW_STACK
This patch converts all helpers that can use ARG_PTR_TO_RAW_STACK as argument
type. For tc programs this is bpf_skb_load_bytes(), bpf_skb_get_tunnel_key(),
bpf_skb_get_tunnel_opt(). For tracing, this optimizes bpf_get_current_comm()
and bpf_probe_read(). The check in bpf_skb_load_bytes() for MAX_BPF_STACK can
also be removed since the verifier already makes sure we stay within bounds
on stack buffers.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-14 21:40:41 -04:00
Michael Ellerman
04cf31a759 ftrace: Make ftrace_location_range() global
In order to support live patching on powerpc we would like to call
ftrace_location_range(), so make it global.

Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-04-14 15:47:05 +10:00
Ingo Molnar
889fac6d67 Linux 4.6-rc3
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Merge tag 'v4.6-rc3' into perf/core, to refresh the tree

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-13 08:57:03 +02:00
Alexei Starovoitov
32bbe0078a bpf: sanitize bpf tracepoint access
during bpf program loading remember the last byte of ctx access
and at the time of attaching the program to tracepoint check that
the program doesn't access bytes beyond defined in tracepoint fields

This also disallows access to __dynamic_array fields, but can be
relaxed in the future.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07 21:04:26 -04:00
Alexei Starovoitov
9940d67c93 bpf: support bpf_get_stackid() and bpf_perf_event_output() in tracepoint programs
needs two wrapper functions to fetch 'struct pt_regs *' to convert
tracepoint bpf context into kprobe bpf context to reuse existing
helper functions

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07 21:04:26 -04:00
Alexei Starovoitov
9fd82b610b bpf: register BPF_PROG_TYPE_TRACEPOINT program type
register tracepoint bpf program type and let it call the same set
of helper functions as BPF_PROG_TYPE_KPROBE

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07 21:04:26 -04:00
Alexei Starovoitov
1e1dcd93b4 perf: split perf_trace_buf_prepare into alloc and update parts
split allows to move expensive update of 'struct trace_entry' to later phase.
Repurpose unused 1st argument of perf_tp_event() to indicate event type.

While splitting use temp variable 'rctx' instead of '*rctx' to avoid
unnecessary loads done by the compiler due to -fno-strict-aliasing

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07 21:04:26 -04:00
Alexei Starovoitov
ec5e099d6e perf: optimize perf_fetch_caller_regs
avoid memset in perf_fetch_caller_regs, since it's the critical path of all tracepoints.
It's called from perf_sw_event_sched, perf_event_task_sched_in and all of perf_trace_##call
with this_cpu_ptr(&__perf_regs[..]) which are zero initialized by perpcu init logic and
subsequent call to perf_arch_fetch_caller_regs initializes the same fields on all archs,
so we can safely drop memset from all of the above cases and move it into
perf_ftrace_function_call that calls it with stack allocated pt_regs.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07 21:04:26 -04:00
Rafael J. Wysocki
9bdcb44e39 cpufreq: schedutil: New governor based on scheduler utilization data
Add a new cpufreq scaling governor, called "schedutil", that uses
scheduler-provided CPU utilization information as input for making
its decisions.

Doing that is possible after commit 34e2c555f3 (cpufreq: Add
mechanism for registering utilization update callbacks) that
introduced cpufreq_update_util() called by the scheduler on
utilization changes (from CFS) and RT/DL task status updates.
In particular, CPU frequency scaling decisions may be based on
the the utilization data passed to cpufreq_update_util() by CFS.

The new governor is relatively simple.

The frequency selection formula used by it depends on whether or not
the utilization is frequency-invariant.  In the frequency-invariant
case the new CPU frequency is given by

	next_freq = 1.25 * max_freq * util / max

where util and max are the last two arguments of cpufreq_update_util().
In turn, if util is not frequency-invariant, the maximum frequency in
the above formula is replaced with the current frequency of the CPU:

	next_freq = 1.25 * curr_freq * util / max

The coefficient 1.25 corresponds to the frequency tipping point at
(util / max) = 0.8.

All of the computations are carried out in the utilization update
handlers provided by the new governor.  One of those handlers is
used for cpufreq policies shared between multiple CPUs and the other
one is for policies with one CPU only (and therefore it doesn't need
to use any extra synchronization means).

The governor supports fast frequency switching if that is supported
by the cpufreq driver in use and possible for the given policy.
In the fast switching case, all operations of the governor take
place in its utilization update handlers.  If fast switching cannot
be used, the frequency switch operations are carried out with the
help of a work item which only calls __cpufreq_driver_target()
(under a mutex) to trigger a frequency update (to a value already
computed beforehand in one of the utilization update handlers).

Currently, the governor treats all of the RT and DL tasks as
"unknown utilization" and sets the frequency to the allowed
maximum when updated from the RT or DL sched classes.  That
heavy-handed approach should be replaced with something more
subtle and specifically targeted at RT and DL tasks.

The governor shares some tunables management code with the
"ondemand" and "conservative" governors and uses some common
definitions from cpufreq_governor.h, but apart from that it
is stand-alone.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2016-04-02 01:09:12 +02:00
Jiri Olsa
0a74c5b3d2 ftrace/perf: Check sample types only for sampling events
Currently we check sample type for ftrace:function events
even if it's not created as a sampling event. That prevents
creating ftrace_function event in counting mode.

Make sure we check sample types only for sampling events.

Before:
  $ sudo perf stat -e ftrace:function ls
  ...

   Performance counter stats for 'ls':

     <not supported>      ftrace:function

         0.001983662 seconds time elapsed

After:
  $ sudo perf stat -e ftrace:function ls
  ...

   Performance counter stats for 'ls':

              44,498      ftrace:function

         0.037534722 seconds time elapsed

Suggested-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1458138873-1553-2-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31 10:30:45 +02:00
Alexander Potapenko
be7635e728 arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.

Move the definition of __irq_entry to <linux/interrupt.h> so that the
users don't need to pull in <linux/ftrace.h>.  Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.

Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-25 16:37:42 -07:00
Linus Torvalds
e46b4e2b46 Nothing major this round. Mostly small clean ups and fixes.
Some visible changes:
 
  A new flag was added to distinguish traces done in NMI context.
 
  Preempt tracer now shows functions where preemption is disabled but
  interrupts are still enabled.
 
 Other notes:
 
  Updates were done to function tracing to allow better performance
  with perf.
 
  Infrastructure code has been added to allow for a new histogram
  feature for recording live trace event histograms that can be
  configured by simple user commands. The feature itself was just
  finished, but needs a round in linux-next before being pulled.
  This only includes some infrastructure changes that will be needed.
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Merge tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "Nothing major this round.  Mostly small clean ups and fixes.

  Some visible changes:

   - A new flag was added to distinguish traces done in NMI context.

   - Preempt tracer now shows functions where preemption is disabled but
     interrupts are still enabled.

  Other notes:

   - Updates were done to function tracing to allow better performance
     with perf.

   - Infrastructure code has been added to allow for a new histogram
     feature for recording live trace event histograms that can be
     configured by simple user commands.  The feature itself was just
     finished, but needs a round in linux-next before being pulled.

     This only includes some infrastructure changes that will be needed"

* tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (22 commits)
  tracing: Record and show NMI state
  tracing: Fix trace_printk() to print when not using bprintk()
  tracing: Remove redundant reset per-CPU buff in irqsoff tracer
  x86: ftrace: Fix the misleading comment for arch/x86/kernel/ftrace.c
  tracing: Fix crash from reading trace_pipe with sendfile
  tracing: Have preempt(irqs)off trace preempt disabled functions
  tracing: Fix return while holding a lock in register_tracer()
  ftrace: Use kasprintf() in ftrace_profile_tracefs()
  ftrace: Update dynamic ftrace calls only if necessary
  ftrace: Make ftrace_hash_rec_enable return update bool
  tracing: Fix typoes in code comment and printk in trace_nop.c
  tracing, writeback: Replace cgroup path to cgroup ino
  tracing: Use flags instead of bool in trigger structure
  tracing: Add an unreg_all() callback to trigger commands
  tracing: Add needs_rec flag to event triggers
  tracing: Add a per-event-trigger 'paused' field
  tracing: Add get_syscall_name()
  tracing: Add event record param to trigger_ops.func()
  tracing: Make event trigger functions available
  tracing: Make ftrace_event_field checking functions available
  ...
2016-03-24 10:52:25 -07:00
Joe Perches
a395d6a7e3 kernel/...: convert pr_warning to pr_warn
Use the more common logging method with the eventual goal of removing
pr_warning altogether.

Miscellanea:

 - Realign arguments
 - Coalesce formats
 - Add missing space between a few coalesced formats

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>	[kernel/power/suspend.c]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Peter Zijlstra
7e6867bf83 tracing: Record and show NMI state
The latency tracer format has a nice column to indicate IRQ state, but
this is not able to tell us about NMI state.

When tracing perf interrupt handlers (which often run in NMI context)
it is very useful to see how the events nest.

Link: http://lkml.kernel.org/r/20160318153022.105068893@infradead.org

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-22 18:04:10 -04:00
Steven Rostedt (Red Hat)
3debb0a9dd tracing: Fix trace_printk() to print when not using bprintk()
The trace_printk() code will allocate extra buffers if the compile detects
that a trace_printk() is used. To do this, the format of the trace_printk()
is saved to the __trace_printk_fmt section, and if that section is bigger
than zero, the buffers are allocated (along with a message that this has
happened).

If trace_printk() uses a format that is not a constant, and thus something
not guaranteed to be around when the print happens, the compiler optimizes
the fmt out, as it is not used, and the __trace_printk_fmt section is not
filled. This means the kernel will not allocate the special buffers needed
for the trace_printk() and the trace_printk() will not write anything to the
tracing buffer.

Adding a "__used" to the variable in the __trace_printk_fmt section will
keep it around, even though it is set to NULL. This will keep the string
from being printed in the debugfs/tracing/printk_formats section as it is
not needed.

Reported-by: Vlastimil Babka <vbabka@suse.cz>
Fixes: 07d777fe8c "tracing: Add percpu buffers for trace_printk()"
Cc: stable@vger.kernel.org # v3.5+
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-22 18:02:40 -04:00
Linus Torvalds
1200b6809d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Highlights:

   1) Support more Realtek wireless chips, from Jes Sorenson.

   2) New BPF types for per-cpu hash and arrap maps, from Alexei
      Starovoitov.

   3) Make several TCP sysctls per-namespace, from Nikolay Borisov.

   4) Allow the use of SO_REUSEPORT in order to do per-thread processing
   of incoming TCP/UDP connections.  The muxing can be done using a
   BPF program which hashes the incoming packet.  From Craig Gallek.

   5) Add a multiplexer for TCP streams, to provide a messaged based
      interface.  BPF programs can be used to determine the message
      boundaries.  From Tom Herbert.

   6) Add 802.1AE MACSEC support, from Sabrina Dubroca.

   7) Avoid factorial complexity when taking down an inetdev interface
      with lots of configured addresses.  We were doing things like
      traversing the entire address less for each address removed, and
      flushing the entire netfilter conntrack table for every address as
      well.

   8) Add and use SKB bulk free infrastructure, from Jesper Brouer.

   9) Allow offloading u32 classifiers to hardware, and implement for
      ixgbe, from John Fastabend.

  10) Allow configuring IRQ coalescing parameters on a per-queue basis,
      from Kan Liang.

  11) Extend ethtool so that larger link mode masks can be supported.
      From David Decotigny.

  12) Introduce devlink, which can be used to configure port link types
      (ethernet vs Infiniband, etc.), port splitting, and switch device
      level attributes as a whole.  From Jiri Pirko.

  13) Hardware offload support for flower classifiers, from Amir Vadai.

  14) Add "Local Checksum Offload".  Basically, for a tunneled packet
      the checksum of the outer header is 'constant' (because with the
      checksum field filled into the inner protocol header, the payload
      of the outer frame checksums to 'zero'), and we can take advantage
      of that in various ways.  From Edward Cree"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1548 commits)
  bonding: fix bond_get_stats()
  net: bcmgenet: fix dma api length mismatch
  net/mlx4_core: Fix backward compatibility on VFs
  phy: mdio-thunder: Fix some Kconfig typos
  lan78xx: add ndo_get_stats64
  lan78xx: handle statistics counter rollover
  RDS: TCP: Remove unused constant
  RDS: TCP: Add sysctl tunables for sndbuf/rcvbuf on rds-tcp socket
  net: smc911x: convert pxa dma to dmaengine
  team: remove duplicate set of flag IFF_MULTICAST
  bonding: remove duplicate set of flag IFF_MULTICAST
  net: fix a comment typo
  ethernet: micrel: fix some error codes
  ip_tunnels, bpf: define IP_TUNNEL_OPTS_MAX and use it
  bpf, dst: add and use dst_tclassid helper
  bpf: make skb->tc_classid also readable
  net: mvneta: bm: clarify dependencies
  cls_bpf: reset class and reuse major in da
  ldmvsw: Checkpatch sunvnet.c and sunvnet_common.c
  ldmvsw: Add ldmvsw.c driver code
  ...
2016-03-19 10:05:34 -07:00
Dmitry Safonov
741f3a69f1 tracing: Remove redundant reset per-CPU buff in irqsoff tracer
There is no reason to do it twice: from commit b6f11df26f
("trace: Call tracing_reset_online_cpus before tracer->init()")
resetting of per-CPU buffers done before tracer->init() call.

tracer->init() calls {irqs,preempt,preemptirqs}off_tracer_init() and it
calls __irqsoff_tracer_init(), which resets per-CPU ringbuffer second
time.
It's slowpath, but anyway.

Link: http://lkml.kernel.org/r/1445278226-16187-1-git-send-email-0x7f454c46@gmail.com

Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 16:39:11 -04:00
Steven Rostedt (Red Hat)
a29054d947 tracing: Fix crash from reading trace_pipe with sendfile
If tracing contains data and the trace_pipe file is read with sendfile(),
then it can trigger a NULL pointer dereference and various BUG_ON within the
VM code.

There's a patch to fix this in the splice_to_pipe() code, but it's also a
good idea to not let that happen from trace_pipe either.

Link: http://lkml.kernel.org/r/1457641146-9068-1-git-send-email-rabin@rab.in

Cc: stable@vger.kernel.org # 2.6.30+
Reported-by: Rabin Vincent <rabin.vincent@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 15:51:42 -04:00
Steven Rostedt (Red Hat)
cb86e05390 tracing: Have preempt(irqs)off trace preempt disabled functions
Joel Fernandes reported that the function tracing of preempt disabled
sections was not being reported when running either the preemptirqsoff or
preemptoff tracers. This was due to the fact that the function tracer
callback for those tracers checked if irqs were disabled before tracing. But
this fails when we want to trace preempt off locations as well.

Joel explained that he wanted to see funcitons where interrupts are enabled
but preemption was disabled. The expected output he wanted:

   <...>-2265    1d.h1 3419us : preempt_count_sub <-irq_exit
   <...>-2265    1d..1 3419us : __do_softirq <-irq_exit
   <...>-2265    1d..1 3419us : msecs_to_jiffies <-__do_softirq
   <...>-2265    1d..1 3420us : irqtime_account_irq <-__do_softirq
   <...>-2265    1d..1 3420us : __local_bh_disable_ip <-__do_softirq
   <...>-2265    1..s1 3421us : run_timer_softirq <-__do_softirq
   <...>-2265    1..s1 3421us : hrtimer_run_pending <-run_timer_softirq
   <...>-2265    1..s1 3421us : _raw_spin_lock_irq <-run_timer_softirq
   <...>-2265    1d.s1 3422us : preempt_count_add <-_raw_spin_lock_irq
   <...>-2265    1d.s2 3422us : _raw_spin_unlock_irq <-run_timer_softirq
   <...>-2265    1..s2 3422us : preempt_count_sub <-_raw_spin_unlock_irq
   <...>-2265    1..s1 3423us : rcu_bh_qs <-__do_softirq
   <...>-2265    1d.s1 3423us : irqtime_account_irq <-__do_softirq
   <...>-2265    1d.s1 3423us : __local_bh_enable <-__do_softirq

There's a comment saying that the irq disabled check is because there's a
possible race that tracing_cpu may be set when the function is executed. But
I don't remember that race. For now, I added a check for preemption being
enabled too to not record the function, as there would be no race if that
was the case. I need to re-investigate this, as I'm now thinking that the
tracing_cpu will always be correct. But no harm in keeping the check for
now, except for the slight performance hit.

Link: http://lkml.kernel.org/r/1457770386-88717-1-git-send-email-agnel.joel@gmail.com

Fixes: 5e6d2b9cfa "tracing: Use one prologue for the preempt irqs off tracer function tracers"
Cc: stable@vget.kernel.org # 2.6.37+
Reported-by: Joel Fernandes <agnel.joel@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 12:47:38 -04:00
Chunyu Hu
c8ca003b2f tracing: Fix return while holding a lock in register_tracer()
commit d39cdd2036 ("tracing: Make tracer_flags use the right set_flag
callback")  introduces a potential mutex deadlock issue, as it forgets to
free the mutex when allocaing the tracer_flags gets fail.

The issue was found by Dan Carpenter through Smatch static code check tool.

Link: http://lkml.kernel.org/r/1457958941-30265-1-git-send-email-chuhu@redhat.com

Fixes: d39cdd2036 ("tracing: Make tracer_flags use the right set_flag callback")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 10:36:21 -04:00
Geliang Tang
6363c6b599 ftrace: Use kasprintf() in ftrace_profile_tracefs()
Use kasprintf() instead of kmalloc() and snprintf().

Link: http://lkml.kernel.org/r/135a7bc36e51fd9eaa57124dd2140285b771f738.1458050835.git.geliangtang@163.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 10:31:34 -04:00
Jiri Olsa
7f50d06bb6 ftrace: Update dynamic ftrace calls only if necessary
Currently dynamic ftrace calls are updated any time
the ftrace_ops is un/registered. If we do  this update
only when it's needed, we save lot of time for perf
system wide ftrace function sampling/counting.

The reason is that for system wide sampling/counting,
perf creates event for each cpu in the system.

Each event then registers separate copy of ftrace_ops,
which ends up in FTRACE_UPDATE_CALLS updates. On servers
with many cpus that means serious stall (240 cpus server):

Counting:
  # time ./perf stat -e ftrace:function -a sleep 1

   Performance counter stats for 'system wide':

              370,663      ftrace:function

          1.401427505 seconds time elapsed

  real    3m51.743s
  user    0m0.023s
  sys     3m48.569s

Sampling:
  # time ./perf record -e ftrace:function -a sleep 1
  [ perf record: Woken up 0 times to write data ]
  Warning:
  Processed 141200 events and lost 5 chunks!

  [ perf record: Captured and wrote 10.703 MB perf.data (135950 samples) ]

  real    2m31.429s
  user    0m0.213s
  sys     2m29.494s

There's no reason to do the FTRACE_UPDATE_CALLS update
for each event in perf case, because all the ftrace_ops
always share the same filter, so the updated calls are
always the same.

It's required that only first ftrace_ops registration
does the FTRACE_UPDATE_CALLS update (also sometimes
the second if the first one used the trampoline), but
the rest can be only cheaply linked into the ftrace_ops
list.

Counting:
  # time ./perf stat -e ftrace:function -a sleep 1

   Performance counter stats for 'system wide':

             398,571      ftrace:function

         1.377503733 seconds time elapsed

  real    0m2.787s
  user    0m0.005s
  sys     0m1.883s

Sampling:
  # time ./perf record -e ftrace:function -a sleep 1
  [ perf record: Woken up 0 times to write data ]
  Warning:
  Processed 261730 events and lost 9 chunks!

  [ perf record: Captured and wrote 19.907 MB perf.data (256293 samples) ]

  real    1m31.948s
  user    0m0.309s
  sys     1m32.051s

Link: http://lkml.kernel.org/r/1458138873-1553-6-git-send-email-jolsa@kernel.org

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 10:30:34 -04:00
Jiri Olsa
84b6d3e614 ftrace: Make ftrace_hash_rec_enable return update bool
Change __ftrace_hash_rec_update to return true in case
we need to update dynamic ftrace call records. It return
false in case no update is needed.

Link: http://lkml.kernel.org/r/1458138873-1553-5-git-send-email-jolsa@kernel.org

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 10:30:15 -04:00
Linus Torvalds
277edbabf6 Power management and ACPI material for v4.6-rc1, part 1
- Redesign of cpufreq governors and the intel_pstate driver to
    make them use callbacks invoked by the scheduler to trigger CPU
    frequency evaluation instead of using per-CPU deferrable timers
    for that purpose (Rafael Wysocki).
 
  - Reorganization and cleanup of cpufreq governor code to make it
    more straightforward and fix some concurrency problems in it
    (Rafael Wysocki, Viresh Kumar).
 
  - Cleanup and improvements of locking in the cpufreq core (Viresh
    Kumar).
 
  - Assorted cleanups in the cpufreq core (Rafael Wysocki, Viresh
    Kumar, Eric Biggers).
 
  - intel_pstate driver updates including fixes, optimizations and a
    modification to make it enable enable hardware-coordinated P-state
    selection (HWP) by default if supported by the processor (Philippe
    Longepe, Srinivas Pandruvada, Rafael Wysocki, Viresh Kumar, Felipe
    Franciosi).
 
  - Operating Performance Points (OPP) framework updates to improve
    its handling of voltage regulators and device clocks and updates
    of the cpufreq-dt driver on top of that (Viresh Kumar, Jon Hunter).
 
  - Updates of the powernv cpufreq driver to fix initialization
    and cleanup problems in it and correct its worker thread handling
    with respect to CPU offline, new powernv_throttle tracepoint
    (Shilpasri Bhat).
 
  - ACPI cpufreq driver optimization and cleanup (Rafael Wysocki).
 
  - ACPICA updates including one fix for a regression introduced
    by previos changes in the ACPICA code (Bob Moore, Lv Zheng,
    David Box, Colin Ian King).
 
  - Support for installing ACPI tables from initrd (Lv Zheng).
 
  - Optimizations of the ACPI CPPC code (Prashanth Prakash, Ashwin
    Chaugule).
 
  - Support for _HID(ACPI0010) devices (ACPI processor containers)
    and ACPI processor driver cleanups (Sudeep Holla).
 
  - Support for ACPI-based enumeration of the AMBA bus (Graeme Gregory,
    Aleksey Makarov).
 
  - Modification of the ACPI PCI IRQ management code to make it treat
    255 in the Interrupt Line register as "not connected" on x86 (as
    per the specification) and avoid attempts to use that value as
    a valid interrupt vector (Chen Fan).
 
  - ACPI APEI fixes related to resource leaks (Josh Hunt).
 
  - Removal of modularity from a few ACPI drivers (BGRT, GHES,
    intel_pmic_crc) that cannot be built as modules in practice (Paul
    Gortmaker).
 
  - PNP framework update to make it treat ACPI_RESOURCE_TYPE_SERIAL_BUS
    as a valid resource type (Harb Abdulhamid).
 
  - New device ID (future AMD I2C controller) in the ACPI driver for
    AMD SoCs (APD) and in the designware I2C driver (Xiangliang Yu).
 
  - Assorted ACPI cleanups (Colin Ian King, Kaiyen Chang, Oleg Drokin).
 
  - cpuidle menu governor optimization to avoid a square root
    computation in it (Rasmus Villemoes).
 
  - Fix for potential use-after-free in the generic device properties
    framework (Heikki Krogerus).
 
  - Updates of the generic power domains (genpd) framework including
    support for multiple power states of a domain, fixes and debugfs
    output improvements (Axel Haslam, Jon Hunter, Laurent Pinchart,
    Geert Uytterhoeven).
 
  - Intel RAPL power capping driver updates to reduce IPI overhead in
    it (Jacob Pan).
 
  - System suspend/hibernation code cleanups (Eric Biggers, Saurabh
    Sengar).
 
  - Year 2038 fix for the process freezer (Abhilash Jindal).
 
  - turbostat utility updates including new features (decoding of more
    registers and CPUID fields, sub-second intervals support, GFX MHz
    and RC6 printout, --out command line option), fixes (syscall jitter
    detection and workaround, reductioin of the number of syscalls made,
    fixes related to Xeon x200 processors, compiler warning fixes) and
    cleanups (Len Brown, Hubert Chrzaniuk, Chen Yu).
 
 /
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Merge tag 'pm+acpi-4.6-rc1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI updates from Rafael Wysocki:
 "This time the majority of changes go into cpufreq and they are
  significant.

  First off, the way CPU frequency updates are triggered is different
  now.  Instead of having to set up and manage a deferrable timer for
  each CPU in the system to evaluate and possibly change its frequency
  periodically, cpufreq governors set up callbacks to be invoked by the
  scheduler on a regular basis (basically on utilization updates).  The
  "old" governors, "ondemand" and "conservative", still do all of their
  work in process context (although that is triggered by the scheduler
  now), but intel_pstate does it all in the callback invoked by the
  scheduler with no need for any additional asynchronous processing.

  Of course, this eliminates the overhead related to the management of
  all those timers, but also it allows the cpufreq governor code to be
  simplified quite a bit.  On top of that, the common code and data
  structures used by the "ondemand" and "conservative" governors are
  cleaned up and made more straightforward and some long-standing and
  quite annoying problems are addressed.  In particular, the handling of
  governor sysfs attributes is modified and the related locking becomes
  more fine grained which allows some concurrency problems to be avoided
  (particularly deadlocks with the core cpufreq code).

  In principle, the new mechanism for triggering frequency updates
  allows utilization information to be passed from the scheduler to
  cpufreq.  Although the current code doesn't make use of it, in the
  works is a new cpufreq governor that will make decisions based on the
  scheduler's utilization data.  That should allow the scheduler and
  cpufreq to work more closely together in the long run.

  In addition to the core and governor changes, cpufreq drivers are
  updated too.  Fixes and optimizations go into intel_pstate, the
  cpufreq-dt driver is updated on top of some modification in the
  Operating Performance Points (OPP) framework and there are fixes and
  other updates in the powernv cpufreq driver.

  Apart from the cpufreq updates there is some new ACPICA material,
  including a fix for a problem introduced by previous ACPICA updates,
  and some less significant changes in the ACPI code, like CPPC code
  optimizations, ACPI processor driver cleanups and support for loading
  ACPI tables from initrd.

  Also updated are the generic power domains framework, the Intel RAPL
  power capping driver and the turbostat utility and we have a bunch of
  traditional assorted fixes and cleanups.

  Specifics:

   - Redesign of cpufreq governors and the intel_pstate driver to make
     them use callbacks invoked by the scheduler to trigger CPU
     frequency evaluation instead of using per-CPU deferrable timers for
     that purpose (Rafael Wysocki).

   - Reorganization and cleanup of cpufreq governor code to make it more
     straightforward and fix some concurrency problems in it (Rafael
     Wysocki, Viresh Kumar).

   - Cleanup and improvements of locking in the cpufreq core (Viresh
     Kumar).

   - Assorted cleanups in the cpufreq core (Rafael Wysocki, Viresh
     Kumar, Eric Biggers).

   - intel_pstate driver updates including fixes, optimizations and a
     modification to make it enable enable hardware-coordinated P-state
     selection (HWP) by default if supported by the processor (Philippe
     Longepe, Srinivas Pandruvada, Rafael Wysocki, Viresh Kumar, Felipe
     Franciosi).

   - Operating Performance Points (OPP) framework updates to improve its
     handling of voltage regulators and device clocks and updates of the
     cpufreq-dt driver on top of that (Viresh Kumar, Jon Hunter).

   - Updates of the powernv cpufreq driver to fix initialization and
     cleanup problems in it and correct its worker thread handling with
     respect to CPU offline, new powernv_throttle tracepoint (Shilpasri
     Bhat).

   - ACPI cpufreq driver optimization and cleanup (Rafael Wysocki).

   - ACPICA updates including one fix for a regression introduced by
     previos changes in the ACPICA code (Bob Moore, Lv Zheng, David Box,
     Colin Ian King).

   - Support for installing ACPI tables from initrd (Lv Zheng).

   - Optimizations of the ACPI CPPC code (Prashanth Prakash, Ashwin
     Chaugule).

   - Support for _HID(ACPI0010) devices (ACPI processor containers) and
     ACPI processor driver cleanups (Sudeep Holla).

   - Support for ACPI-based enumeration of the AMBA bus (Graeme Gregory,
     Aleksey Makarov).

   - Modification of the ACPI PCI IRQ management code to make it treat
     255 in the Interrupt Line register as "not connected" on x86 (as
     per the specification) and avoid attempts to use that value as a
     valid interrupt vector (Chen Fan).

   - ACPI APEI fixes related to resource leaks (Josh Hunt).

   - Removal of modularity from a few ACPI drivers (BGRT, GHES,
     intel_pmic_crc) that cannot be built as modules in practice (Paul
     Gortmaker).

   - PNP framework update to make it treat ACPI_RESOURCE_TYPE_SERIAL_BUS
     as a valid resource type (Harb Abdulhamid).

   - New device ID (future AMD I2C controller) in the ACPI driver for
     AMD SoCs (APD) and in the designware I2C driver (Xiangliang Yu).

   - Assorted ACPI cleanups (Colin Ian King, Kaiyen Chang, Oleg Drokin).

   - cpuidle menu governor optimization to avoid a square root
     computation in it (Rasmus Villemoes).

   - Fix for potential use-after-free in the generic device properties
     framework (Heikki Krogerus).

   - Updates of the generic power domains (genpd) framework including
     support for multiple power states of a domain, fixes and debugfs
     output improvements (Axel Haslam, Jon Hunter, Laurent Pinchart,
     Geert Uytterhoeven).

   - Intel RAPL power capping driver updates to reduce IPI overhead in
     it (Jacob Pan).

   - System suspend/hibernation code cleanups (Eric Biggers, Saurabh
     Sengar).

   - Year 2038 fix for the process freezer (Abhilash Jindal).

   - turbostat utility updates including new features (decoding of more
     registers and CPUID fields, sub-second intervals support, GFX MHz
     and RC6 printout, --out command line option), fixes (syscall jitter
     detection and workaround, reductioin of the number of syscalls
     made, fixes related to Xeon x200 processors, compiler warning
     fixes) and cleanups (Len Brown, Hubert Chrzaniuk, Chen Yu)"

* tag 'pm+acpi-4.6-rc1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (182 commits)
  tools/power turbostat: bugfix: TDP MSRs print bits fixing
  tools/power turbostat: correct output for MSR_NHM_SNB_PKG_CST_CFG_CTL dump
  tools/power turbostat: call __cpuid() instead of __get_cpuid()
  tools/power turbostat: indicate SMX and SGX support
  tools/power turbostat: detect and work around syscall jitter
  tools/power turbostat: show GFX%rc6
  tools/power turbostat: show GFXMHz
  tools/power turbostat: show IRQs per CPU
  tools/power turbostat: make fewer systems calls
  tools/power turbostat: fix compiler warnings
  tools/power turbostat: add --out option for saving output in a file
  tools/power turbostat: re-name "%Busy" field to "Busy%"
  tools/power turbostat: Intel Xeon x200: fix turbo-ratio decoding
  tools/power turbostat: Intel Xeon x200: fix erroneous bclk value
  tools/power turbostat: allow sub-sec intervals
  ACPI / APEI: ERST: Fixed leaked resources in erst_init
  ACPI / APEI: Fix leaked resources
  intel_pstate: Do not skip samples partially
  intel_pstate: Remove freq calculation from intel_pstate_calc_busy()
  intel_pstate: Move intel_pstate_calc_busy() into get_target_pstate_use_performance()
  ...
2016-03-16 14:10:53 -07:00
Linus Torvalds
e71c2c1eeb Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "Main kernel side changes:

   - Big reorganization of the x86 perf support code.  The old code grew
     organically deep inside arch/x86/kernel/cpu/perf* and its naming
     became somewhat messy.

     The new location is under arch/x86/events/, using the following
     cleaner hierarchy of source code files:

       perf/x86: Move perf_event.c .................. => x86/events/core.c
       perf/x86: Move perf_event_amd.c .............. => x86/events/amd/core.c
       perf/x86: Move perf_event_amd_ibs.c .......... => x86/events/amd/ibs.c
       perf/x86: Move perf_event_amd_iommu.[ch] ..... => x86/events/amd/iommu.[ch]
       perf/x86: Move perf_event_amd_uncore.c ....... => x86/events/amd/uncore.c
       perf/x86: Move perf_event_intel_bts.c ........ => x86/events/intel/bts.c
       perf/x86: Move perf_event_intel.c ............ => x86/events/intel/core.c
       perf/x86: Move perf_event_intel_cqm.c ........ => x86/events/intel/cqm.c
       perf/x86: Move perf_event_intel_cstate.c ..... => x86/events/intel/cstate.c
       perf/x86: Move perf_event_intel_ds.c ......... => x86/events/intel/ds.c
       perf/x86: Move perf_event_intel_lbr.c ........ => x86/events/intel/lbr.c
       perf/x86: Move perf_event_intel_pt.[ch] ...... => x86/events/intel/pt.[ch]
       perf/x86: Move perf_event_intel_rapl.c ....... => x86/events/intel/rapl.c
       perf/x86: Move perf_event_intel_uncore.[ch] .. => x86/events/intel/uncore.[ch]
       perf/x86: Move perf_event_intel_uncore_nhmex.c => x86/events/intel/uncore_nmhex.c
       perf/x86: Move perf_event_intel_uncore_snb.c   => x86/events/intel/uncore_snb.c
       perf/x86: Move perf_event_intel_uncore_snbep.c => x86/events/intel/uncore_snbep.c
       perf/x86: Move perf_event_knc.c .............. => x86/events/intel/knc.c
       perf/x86: Move perf_event_p4.c ............... => x86/events/intel/p4.c
       perf/x86: Move perf_event_p6.c ............... => x86/events/intel/p6.c
       perf/x86: Move perf_event_msr.c .............. => x86/events/msr.c

     (Borislav Petkov)

   - Update various x86 PMU constraint and hw support details (Stephane
     Eranian)

   - Optimize kprobes for BPF execution (Martin KaFai Lau)

   - Rewrite, refactor and fix the Intel uncore PMU driver code (Thomas
     Gleixner)

   - Rewrite, refactor and fix the Intel RAPL PMU code (Thomas Gleixner)

   - Various fixes and smaller cleanups.

  There are lots of perf tooling updates as well.  A few highlights:

  perf report/top:

     - Hierarchy histogram mode for 'perf top' and 'perf report',
       showing multiple levels, one per --sort entry: (Namhyung Kim)

       On a mostly idle system:

         # perf top --hierarchy -s comm,dso

       Then expand some levels and use 'P' to take a snapshot:

         # cat perf.hist.0
         -  92.32%         perf
               58.20%         perf
               22.29%         libc-2.22.so
                5.97%         [kernel]
                4.18%         libelf-0.165.so
                1.69%         [unknown]
         -   4.71%         qemu-system-x86
                3.10%         [kernel]
                1.60%         qemu-system-x86_64 (deleted)
         +   2.97%         swapper
         #

     - Add 'L' hotkey to dynamicly set the percent threshold for
       histogram entries and callchains, i.e.  dynamicly do what the
       --percent-limit command line option to 'top' and 'report' does.
       (Namhyung Kim)

  perf mem:

     - Allow specifying events via -e in 'perf mem record', also listing
       what events can be specified via 'perf mem record -e list' (Jiri
       Olsa)

  perf record:

     - Add 'perf record' --all-user/--all-kernel options, so that one
       can tell that all the events in the command line should be
       restricted to the user or kernel levels (Jiri Olsa), i.e.:

         perf record -e cycles:u,instructions:u

       is equivalent to:

         perf record --all-user -e cycles,instructions

     - Make 'perf record' collect CPU cache info in the perf.data file header:

         $ perf record usleep 1
         [ perf record: Woken up 1 times to write data ]
         [ perf record: Captured and wrote 0.017 MB perf.data (7 samples) ]
         $ perf report --header-only -I | tail -10 | head -8
         # CPU cache info:
         #  L1 Data                 32K [0-1]
         #  L1 Instruction          32K [0-1]
         #  L1 Data                 32K [2-3]
         #  L1 Instruction          32K [2-3]
         #  L2 Unified             256K [0-1]
         #  L2 Unified             256K [2-3]
         #  L3 Unified            4096K [0-3]

       Will be used in 'perf c2c' and eventually in 'perf diff' to
       allow, for instance running the same workload in multiple
       machines and then when using 'diff' show the hardware difference.
       (Jiri Olsa)

     - Improved support for Java, using the JVMTI agent library to do
       jitdumps that then will be inserted in synthesized
       PERF_RECORD_MMAP2 events via 'perf inject' pointed to synthesized
       ELF files stored in ~/.debug and keyed with build-ids, to allow
       symbol resolution and even annotation with source line info, see
       the changeset comments to see how to use it (Stephane Eranian)

  perf script/trace:

     - Decode data_src values (e.g.  perf.data files generated by 'perf
       mem record') in 'perf script': (Jiri Olsa)

         # perf script
           perf 693 [1] 4.088652: 1 cpu/mem-loads,ldlat=30/P: ffff88007d0b0f40 68100142 L1 hit|SNP None|TLB L1 or L2 hit|LCK No <SNIP>
                                                                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
     - Improve support to 'data_src', 'weight' and 'addr' fields in
       'perf script' (Jiri Olsa)

     - Handle empty print fmts in 'perf script -s' i.e. when running
       python or perl scripts (Taeung Song)

  perf stat:

     - 'perf stat' now shows shadow metrics (insn per cycle, etc) in
       interval mode too.  E.g:

         # perf stat -I 1000 -e instructions,cycles sleep 1
         #         time   counts unit events
            1.000215928  519,620      instructions     #  0.69 insn per cycle
            1.000215928  752,003      cycles
         <SNIP>

     - Port 'perf kvm stat' to PowerPC (Hemant Kumar)

     - Implement CSV metrics output in 'perf stat' (Andi Kleen)

  perf BPF support:

     - Support converting data from bpf events in 'perf data' (Wang Nan)

     - Print bpf-output events in 'perf script': (Wang Nan).

         # perf record -e bpf-output/no-inherit,name=evt/ -e ./test_bpf_output_3.c/map:channel.event=evt/ usleep 1000
         # perf script
            usleep  4882 21384.532523:   evt:  ffffffff810e97d1 sys_nanosleep ([kernel.kallsyms])
             BPF output: 0000: 52 61 69 73 65 20 61 20  Raise a
                         0008: 42 50 46 20 65 76 65 6e  BPF even
                         0010: 74 21 00 00              t!..
             BPF string: "Raise a BPF event!"
         #

     - Add API to set values of map entries in a BPF object, be it
       individual map slots or ranges (Wang Nan)

     - Introduce support for the 'bpf-output' event (Wang Nan)

     - Add glue to read perf events in a BPF program (Wang Nan)

     - Improve support for bpf-output events in 'perf trace' (Wang Nan)

  ... and tons of other changes as well - see the shortlog and git log
  for details!"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (342 commits)
  perf stat: Add --metric-only support for -A
  perf stat: Implement --metric-only mode
  perf stat: Document CSV format in manpage
  perf hists browser: Check sort keys before hot key actions
  perf hists browser: Allow thread filtering for comm sort key
  perf tools: Add sort__has_comm variable
  perf tools: Recalc total periods using top-level entries in hierarchy
  perf tools: Remove nr_sort_keys field
  perf hists browser: Cleanup hist_browser__fprintf_hierarchy_entry()
  perf tools: Remove hist_entry->fmt field
  perf tools: Fix command line filters in hierarchy mode
  perf tools: Add more sort entry check functions
  perf tools: Fix hist_entry__filter() for hierarchy
  perf jitdump: Build only on supported archs
  tools lib traceevent: Add '~' operation within arg_num_eval()
  perf tools: Omit unnecessary cast in perf_pmu__parse_scale
  perf tools: Pass perf_hpp_list all the way through setup_sort_list
  perf tools: Fix perf script python database export crash
  perf jitdump: DWARF is also needed
  perf bench mem: Prepare the x86-64 build for upstream memcpy_mcsafe() changes
  ...
2016-03-14 17:58:53 -07:00
Rafael J. Wysocki
4ed3900427 Merge branch 'pm-cpufreq'
* pm-cpufreq: (94 commits)
  intel_pstate: Do not skip samples partially
  intel_pstate: Remove freq calculation from intel_pstate_calc_busy()
  intel_pstate: Move intel_pstate_calc_busy() into get_target_pstate_use_performance()
  intel_pstate: Optimize calculation for max/min_perf_adj
  intel_pstate: Remove extra conversions in pid calculation
  cpufreq: Move scheduler-related code to the sched directory
  Revert "cpufreq: postfix policy directory with the first CPU in related_cpus"
  cpufreq: Reduce cpufreq_update_util() overhead a bit
  cpufreq: Select IRQ_WORK if CPU_FREQ_GOV_COMMON is set
  cpufreq: Remove 'policy->governor_enabled'
  cpufreq: Rename __cpufreq_governor() to cpufreq_governor()
  cpufreq: Relocate handle_update() to kill its declaration
  cpufreq: governor: Drop unnecessary checks from show() and store()
  cpufreq: governor: Fix race in dbs_update_util_handler()
  cpufreq: governor: Make gov_set_update_util() static
  cpufreq: governor: Narrow down the dbs_data_mutex coverage
  cpufreq: governor: Make dbs_data_mutex static
  cpufreq: governor: Relocate definitions of tuners structures
  cpufreq: governor: Move per-CPU data to the common code
  cpufreq: governor: Make governor private data per-policy
  ...
2016-03-14 14:22:03 +01:00
Alexei Starovoitov
b121d1e74d bpf: prevent kprobe+bpf deadlocks
if kprobe is placed within update or delete hash map helpers
that hold bucket spin lock and triggered bpf program is trying to
grab the spinlock for the same bucket on the same cpu, it will
deadlock.
Fix it by extending existing recursion prevention mechanism.

Note, map_lookup and other tracing helpers don't have this problem,
since they don't hold any locks and don't modify global data.
bpf_trace_printk has its own recursive check and ok as well.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08 15:28:30 -05:00
David S. Miller
810813c47a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several cases of overlapping changes, as well as one instance
(vxlan) of a bug fix in 'net' overlapping with code movement
in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08 12:34:12 -05:00
Chunyu Hu
1cf8067b54 tracing: Fix typoes in code comment and printk in trace_nop.c
echo nop > /sys/kernel/debug/tracing/options/current_tracer
echo 1 > /sys/kernel/debug/tracing/options/test_nop_accept
echo 0 > /sys/kernel/debug/tracing/options/test_nop_accept
echo 1 > /sys/kernel/debug/tracing/options/test_nop_refuse

Before the fix, the dmesg is a bit ugly since a align issue.

[  191.973081] nop_test_accept flag set to 1: we accept. Now cat trace_options to see the result
[  195.156942] nop_test_refuse flag set to 1: we refuse.Now cat trace_options to see the result

After the fix, the dmesg will show aligned log for nop_test_refuse and nop_test_accept.

[ 2718.032413] nop_test_refuse flag set to 1: we refuse. Now cat trace_options to see the result
[ 2734.253360] nop_test_accept flag set to 1: we accept. Now cat trace_options to see the result

Link: http://lkml.kernel.org/r/1457444222-8654-2-git-send-email-chuhu@redhat.com

Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-08 11:23:57 -05:00
Steven Rostedt (Red Hat)
353206f5ca tracing: Use flags instead of bool in trigger structure
gcc isn't known for handling bool in structures. Instead of using bool, use
an integer mask and use bit flags instead.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-08 11:19:36 -05:00
Tom Zanussi
a88e1cfb1d tracing: Add an unreg_all() callback to trigger commands
Add a new unreg_all() callback that can be used to remove all
command-specific triggers from an event and arrange to have it called
whenever a trigger file is opened with O_TRUNC set.

Commands that don't want truncate semantics, or existing commands that
don't implement this function simply do nothing and their triggers
remain intact.

Link: http://lkml.kernel.org/r/2b7d62854d01f28c19185e1bbb8f826f385edfba.1449767187.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-08 11:19:35 -05:00
Tom Zanussi
a5863dae84 tracing: Add needs_rec flag to event triggers
Add a new needs_rec flag for triggers that require unconditional
access to trace records in order to function.

Normally a trigger requires access to the contents of a trace record
only if it has a filter associated with it (since filters need the
contents of a record in order to make a filtering decision).  Some
types of triggers, such as 'hist' triggers, require access to trace
record contents independent of the presence of filters, so add a new
flag for those triggers.

Link: http://lkml.kernel.org/r/7be8fa38f9b90fdb6c47ca0f98d20a07b9fd512b.1449767187.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-08 11:19:34 -05:00
Tom Zanussi
104f281044 tracing: Add a per-event-trigger 'paused' field
Add a simple per-trigger 'paused' flag, allowing individual triggers
to pause.  We could leave it to individual triggers that need this
functionality to do it themselves, but we also want to allow other
events to control pausing, so add it to the trigger data.

Link: http://lkml.kernel.org/r/fed37e4879684d7dcc57fe00ce0cbf170032b06d.1449767187.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-08 11:19:33 -05:00
Tom Zanussi
dbfeaa7aba tracing: Add get_syscall_name()
Add a utility function to grab the syscall name from the syscall
metadata, given a syscall id.

Link: http://lkml.kernel.org/r/be26a8dfe3f15e16a837799f1c1e2b4d62742843.1449767187.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-08 11:19:32 -05:00
Tom Zanussi
c4a5923055 tracing: Add event record param to trigger_ops.func()
Some triggers may need access to the trace event, so pass it in.  Also
fix up the existing trigger funcs and their callers.

Link: http://lkml.kernel.org/r/543e31e9fc445ef61077421ab219033401c39846.1449767187.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-08 11:19:31 -05:00
Tom Zanussi
ab4bf00892 tracing: Make event trigger functions available
Make various event trigger utility functions available outside of
trace_events_trigger.c so that new triggers can be defined outside of
that file.

Link: http://lkml.kernel.org/r/4a40c1695dd43cac6cd475d72e13ffe30ba84bff.1449767187.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-08 11:19:30 -05:00
Tom Zanussi
4ef56902fb tracing: Make ftrace_event_field checking functions available
Make is_string_field() and is_function_field() accessible outside of
trace_event_filters.c for other users of ftrace_event_fields.

Link: http://lkml.kernel.org/r/2d3f00d3311702e556e82eed7754bae6f017939f.1449767187.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-08 11:19:29 -05:00
Chunyu Hu
d39cdd2036 tracing: Make tracer_flags use the right set_flag callback
When I was updating the ftrace_stress test of ltp. I encountered
a strange phenomemon, excute following steps:

echo nop > /sys/kernel/debug/tracing/current_tracer
echo 0 > /sys/kernel/debug/tracing/options/funcgraph-cpu
bash: echo: write error: Invalid argument

check dmesg:
[ 1024.903855] nop_test_refuse flag set to 0: we refuse.Now cat trace_options to see the result

The reason is that the trace option test will randomly setup trace
option under tracing/options no matter what the current_tracer is.
but the set_tracer_option is always using the set_flag callback
from the current_tracer. This patch adds a pointer to tracer_flags
and make it point to the tracer it belongs to. When the option is
setup, the set_flag of the right tracer will be used no matter
what the the current_tracer is.

And the old dummy_tracer_flags is used for all the tracers which
doesn't have a tracer_flags, having issue to use it to save the
pointer of a tracer. So remove it and use dynamic dummy tracer_flags
for tracers needing a dummy tracer_flags, as a result, there are no
tracers sharing tracer_flags, so remove the check code.

And save the current tracer to trace_option_dentry seems not good as
it may waste mem space when mount the debug/trace fs more than one time.

Link: http://lkml.kernel.org/r/1457444222-8654-1-git-send-email-chuhu@redhat.com

Signed-off-by: Chunyu Hu <chuhu@redhat.com>
[ Fixed up function tracer options to work with the change ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-08 11:19:08 -05:00
Linus Torvalds
78baab7aa8 A feature was added in 4.3 that allowed users to filter trace points on
a tasks "comm" field. But this prevented filtering on a comm field that
 is within a trace event (like sched_migrate_task).
 
 When trying to filter on when a program migrated, this change prevented
 the filtering of the sched_migrate_task.
 
 To fix this, the event fields are examined first, and then the extra fields
 like "comm" and "cpu" are examined. Also, instead of testing to assign
 the comm filter function based on the field's name, the generic comm field
 is given a new filter type (FILTER_COMM). When this field is used to filter
 the type is checked. The same is done for the cpu filter field.
 
 Two new special filter types are added: "COMM" and "CPU". This allows users
 to still filter the tasks comm for events that have "comm" as one of their
 fields, in cases that users would like to filter sched_migrate_task on the
 comm of the task that called the event, and not the comm of the task that
 is being migrated.
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Merge tag 'trace-fixes-v4.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "A feature was added in 4.3 that allowed users to filter trace points
  on a tasks "comm" field.  But this prevented filtering on a comm field
  that is within a trace event (like sched_migrate_task).

  When trying to filter on when a program migrated, this change
  prevented the filtering of the sched_migrate_task.

  To fix this, the event fields are examined first, and then the extra
  fields like "comm" and "cpu" are examined.  Also, instead of testing
  to assign the comm filter function based on the field's name, the
  generic comm field is given a new filter type (FILTER_COMM).  When
  this field is used to filter the type is checked.  The same is done
  for the cpu filter field.

  Two new special filter types are added: "COMM" and "CPU".  This allows
  users to still filter the tasks comm for events that have "comm" as
  one of their fields, in cases that users would like to filter
  sched_migrate_task on the comm of the task that called the event, and
  not the comm of the task that is being migrated"

* tag 'trace-fixes-v4.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Do not have 'comm' filter override event 'comm' field
2016-03-04 16:57:04 -08:00
Steven Rostedt (Red Hat)
e57cbaf0eb tracing: Do not have 'comm' filter override event 'comm' field
Commit 9f61668073 "tracing: Allow triggers to filter for CPU ids and
process names" added a 'comm' filter that will filter events based on the
current tasks struct 'comm'. But this now hides the ability to filter events
that have a 'comm' field too. For example, sched_migrate_task trace event.
That has a 'comm' field of the task to be migrated.

 echo 'comm == "bash"' > events/sched_migrate_task/filter

will now filter all sched_migrate_task events for tasks named "bash" that
migrates other tasks (in interrupt context), instead of seeing when "bash"
itself gets migrated.

This fix requires a couple of changes.

1) Change the look up order for filter predicates to look at the events
   fields before looking at the generic filters.

2) Instead of basing the filter function off of the "comm" name, have the
   generic "comm" filter have its own filter_type (FILTER_COMM). Test
   against the type instead of the name to assign the filter function.

3) Add a new "COMM" filter that works just like "comm" but will filter based
   on the current task, even if the trace event contains a "comm" field.

Do the same for "cpu" field, adding a FILTER_CPU and a filter "CPU".

Cc: stable@vger.kernel.org # v4.3+
Fixes: 9f61668073 "tracing: Allow triggers to filter for CPU ids and process names"
Reported-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-04 09:57:10 -05:00
Taeung Song
026842d148 tracing/syscalls: Rename "/format" tracepoint field name "nr" to "__syscall_nr:
Some tracepoint have multiple fields with the same name, "nr", the first
one is a unique syscall ID, the other is a syscall argument:

  # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_io_getevents/format
  name: sys_enter_io_getevents
  ID: 747
  format:
 	field:unsigned short common_type;	offset:0;	size:2;	signed:0;
 	field:unsigned char common_flags;	offset:2;	size:1;	signed:0;
 	field:unsigned char common_preempt_count;	offset:3;	size:1;	signed:0;
 	field:int common_pid;	offset:4;	size:4;	signed:1;

 	field:int nr;	offset:8;	size:4;	signed:1;
 	field:aio_context_t ctx_id;	offset:16;	size:8;	signed:0;
 	field:long min_nr;	offset:24;	size:8;	signed:0;
 	field:long nr;	offset:32;	size:8;	signed:0;
 	field:struct io_event * events;	offset:40;	size:8;	signed:0;
 	field:struct timespec * timeout;	offset:48;	size:8;	signed:0;

  print fmt: "ctx_id: 0x%08lx, min_nr: 0x%08lx, nr: 0x%08lx, events: 0x%08lx, timeout: 0x%08lx", ((unsigned long)(REC->ctx_id)), ((unsigned long)(REC->min_nr)), ((unsigned long)(REC->nr)), ((unsigned long)(REC->events)), ((unsigned long)(REC->timeout))
  #

Fix it by renaming the "/format" common tracepoint field "nr" to "__syscall_nr".

Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
[ Do not rename the struct member, just the '/format' field name ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160226132301.3ae065a4@gandalf.local.home
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-29 11:34:53 -03:00
Ingo Molnar
0a7348925f Linux 4.5-rc6
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Merge tag 'v4.5-rc6' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-29 09:04:01 +01:00
Linus Torvalds
5bb9871eb8 Another small bug reported to me by Chunyu Hu.
When perf added a "reg" function to the function tracing event (not a
 tracepoint), it caused that event to be displayed as a tracepoint and
 could cause errors in tracepoint handling. That was solved by adding a
 flag to ignore ftrace non-tracepoint events. But that flag was missed
 when displaying events in available_events, which should only contain
 tracepoint events.
 
 This broke a documented way to enable all events with:
 
   cat available_events > set_event
 
 As the function non-tracepoint event would cause that to error out.
 The commit here fixes that by having the available_events file not list
 events that have the ignore flag set.
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Merge tag 'trace-fixes-v4.5-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Another small bug reported to me by Chunyu Hu.

  When perf added a "reg" function to the function tracing event (not a
  tracepoint), it caused that event to be displayed as a tracepoint and
  could cause errors in tracepoint handling.  That was solved by adding
  a flag to ignore ftrace non-tracepoint events.  But that flag was
  missed when displaying events in available_events, which should only
  contain tracepoint events.

  This broke a documented way to enable all events with:

      cat available_events > set_event

  As the function non-tracepoint event would cause that to error out.
  The commit here fixes that by having the available_events file not
  list events that have the ignore flag set"

* tag 'trace-fixes-v4.5-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix showing function event in available_events
2016-02-25 20:12:09 -08:00
Steven Rostedt (Red Hat)
d045437a16 tracing: Fix showing function event in available_events
The ftrace:function event is only displayed for parsing the function tracer
data. It is not used to enable function tracing, and does not include an
"enable" file in its event directory.

Originally, this event was kept separate from other events because it did
not have a ->reg parameter. But perf added a "reg" parameter for its use
which caused issues, because it made the event available to functions where
it was not compatible for.

Commit 9b63776fa3 "tracing: Do not enable function event with enable"
added a TRACE_EVENT_FL_IGNORE_ENABLE flag that prevented the function event
from being enabled by normal trace events. But this commit missed keeping
the function event from being displayed by the "available_events" directory,
which is used to show what events can be enabled by set_event.

One documented way to enable all events is to:

 cat available_events > set_event

But because the function event is displayed in the available_events, this
now causes an INVALID error:

 cat: write error: Invalid argument

Reported-by: Chunyu Hu <chuhu@redhat.com>
Fixes: 9b63776fa3 "tracing: Do not enable function event with enable"
Cc: stable@vger.kernel.org # 3.4+
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-02-24 09:17:11 -05:00
David S. Miller
b633353115 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/phy/bcm7xxx.c
	drivers/net/phy/marvell.c
	drivers/net/vxlan.c

All three conflicts were cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-23 00:09:14 -05:00
Linus Torvalds
4de8ebeff8 Two more small fixes.
One is by Yang Shi who added a READ_ONCE_NOCHECK() to the scan of the
 stack made by the stack tracer. As the stack tracer scans the entire
 kernel stack, KASAN triggers seeing it as a "stack out of bounds" error.
 As the scan is looking at the contents of the stack from parent functions.
 The NOCHECK() tells KASAN that this is done on purpose, and is not some
 kind of stack overflow.
 
 The second fix is to the ftrace selftests, to retrieve the PID of executed
 commands from the shell with "$!" and not by parsing "jobs".
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Merge tag 'trace-fixes-v4.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Two more small fixes.

  One is by Yang Shi who added a READ_ONCE_NOCHECK() to the scan of the
  stack made by the stack tracer.  As the stack tracer scans the entire
  kernel stack, KASAN triggers seeing it as a "stack out of bounds"
  error.  As the scan is looking at the contents of the stack from
  parent functions.  The NOCHECK() tells KASAN that this is done on
  purpose, and is not some kind of stack overflow.

  The second fix is to the ftrace selftests, to retrieve the PID of
  executed commands from the shell with '$!' and not by parsing 'jobs'"

* tag 'trace-fixes-v4.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing, kasan: Silence Kasan warning in check_stack of stack_tracer
  ftracetest: Fix instance test to use proper shell command for pids
2016-02-22 14:09:18 -08:00
Alexei Starovoitov
d5a3b1f691 bpf: introduce BPF_MAP_TYPE_STACK_TRACE
add new map type to store stack traces and corresponding helper
bpf_get_stackid(ctx, map, flags) - walk user or kernel stack and return id
@ctx: struct pt_regs*
@map: pointer to stack_trace map
@flags: bits 0-7 - numer of stack frames to skip
        bit 8 - collect user stack instead of kernel
        bit 9 - compare stacks by hash only
        bit 10 - if two different stacks hash into the same stackid
                 discard old
        other bits - reserved
Return: >= 0 stackid on success or negative error

stackid is a 32-bit integer handle that can be further combined with
other data (including other stackid) and used as a key into maps.

Userspace will access stackmap using standard lookup/delete syscall commands to
retrieve full stack trace for given stackid.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-20 00:21:44 -05:00
Yang Shi
6e22c83664 tracing, kasan: Silence Kasan warning in check_stack of stack_tracer
When enabling stack trace via "echo 1 > /proc/sys/kernel/stack_tracer_enabled",
the below KASAN warning is triggered:

BUG: KASAN: stack-out-of-bounds in check_stack+0x344/0x848 at addr ffffffc0689ebab8
Read of size 8 by task ksoftirqd/4/29
page:ffffffbdc3a27ac0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x0()
page dumped because: kasan: bad access detected
CPU: 4 PID: 29 Comm: ksoftirqd/4 Not tainted 4.5.0-rc1 #129
Hardware name: Freescale Layerscape 2085a RDB Board (DT)
Call trace:
[<ffffffc000091300>] dump_backtrace+0x0/0x3a0
[<ffffffc0000916c4>] show_stack+0x24/0x30
[<ffffffc0009bbd78>] dump_stack+0xd8/0x168
[<ffffffc000420bb0>] kasan_report_error+0x6a0/0x920
[<ffffffc000421688>] kasan_report+0x70/0xb8
[<ffffffc00041f7f0>] __asan_load8+0x60/0x78
[<ffffffc0002e05c4>] check_stack+0x344/0x848
[<ffffffc0002e0c8c>] stack_trace_call+0x1c4/0x370
[<ffffffc0002af558>] ftrace_ops_no_ops+0x2c0/0x590
[<ffffffc00009f25c>] ftrace_graph_call+0x0/0x14
[<ffffffc0000881bc>] fpsimd_thread_switch+0x24/0x1e8
[<ffffffc000089864>] __switch_to+0x34/0x218
[<ffffffc0011e089c>] __schedule+0x3ac/0x15b8
[<ffffffc0011e1f6c>] schedule+0x5c/0x178
[<ffffffc0001632a8>] smpboot_thread_fn+0x350/0x960
[<ffffffc00015b518>] kthread+0x1d8/0x2b0
[<ffffffc0000874d0>] ret_from_fork+0x10/0x40
Memory state around the buggy address:
 ffffffc0689eb980: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 f4 f4 f4
 ffffffc0689eba00: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
>ffffffc0689eba80: 00 00 f1 f1 f1 f1 00 f4 f4 f4 f3 f3 f3 f3 00 00
                                        ^
 ffffffc0689ebb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffffc0689ebb80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

The stacker tracer traverses the whole kernel stack when saving the max stack
trace. It may touch the stack red zones to cause the warning. So, just disable
the instrumentation to silence the warning.

Link: http://lkml.kernel.org/r/1455309960-18930-1-git-send-email-yang.shi@linaro.org

Signed-off-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-02-19 12:36:44 -05:00
Linus Torvalds
705d43dbe1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
Pull livepatching fixes from Jiri Kosina:

 - regression (from 4.4) fix for ordering issue, introduced by an
   earlier ftrace change, that broke live patching of modules.

   The fix replaces the ftrace module notifier by direct call in order
   to make the ordering guaranteed and well-defined.  The patch, from
   Jessica Yu, has been acked both by Steven and Rusty

 - error message fix from Miroslav Benes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  ftrace/module: remove ftrace module notifier
  livepatch: change the error message in asm/livepatch.h header files
2016-02-18 16:34:15 -08:00
Jessica Yu
7dcd182bec ftrace/module: remove ftrace module notifier
Remove the ftrace module notifier in favor of directly calling
ftrace_module_enable() and ftrace_release_mod() in the module loader.
Hard-coding the function calls directly in the module loader removes
dependence on the module notifier call chain and provides better
visibility and control over what gets called when, which is important
to kernel utilities such as livepatch.

This fixes a notifier ordering issue in which the ftrace module notifier
(and hence ftrace_module_enable()) for coming modules was being called
after klp_module_notify(), which caused livepatch modules to initialize
incorrectly. This patch removes dependence on the module notifier call
chain in favor of hard coding the corresponding function calls in the
module loader. This ensures that ftrace and livepatch code get called in
the correct order on patch module load and unload.

Fixes: 5156dca34a ("ftrace: Fix the race between ftrace and insmod")
Signed-off-by: Jessica Yu <jeyu@redhat.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2016-02-17 22:14:06 +01:00
Rafael J. Wysocki
b2a3b193b7 Merge branch 'pm-opp' into pm-cpufreq 2016-02-11 00:24:00 +01:00
Martin KaFai Lau
a7636d9ecf kprobes: Optimize hot path by using percpu counter to collect 'nhit' statistics
When doing ebpf+kprobe on some hot TCP functions (e.g.
tcp_rcv_established), the kprobe_dispatcher() function
shows up in 'perf report'.

In kprobe_dispatcher(), there is a lot of cache bouncing
on 'tk->nhit++'.  'tk->nhit' and 'tk->tp.flags' also share
the same cacheline.

perf report (cycles:pp):

	8.30%  ipv4_dst_check
	4.74%  copy_user_enhanced_fast_string
	3.93%  dst_release
	2.80%  tcp_v4_rcv
	2.31%  queued_spin_lock_slowpath
	2.30%  _raw_spin_lock
	1.88%  mlx4_en_process_rx_cq
	1.84%  eth_get_headlen
	1.81%  ip_rcv_finish
	~~~~
	1.71%  kprobe_dispatcher
	~~~~
	1.55%  mlx4_en_xmit
	1.09%  __probe_kernel_read

perf report after patch:

	9.15%  ipv4_dst_check
	5.00%  copy_user_enhanced_fast_string
	4.12%  dst_release
	2.96%  tcp_v4_rcv
	2.50%  _raw_spin_lock
	2.39%  queued_spin_lock_slowpath
	2.11%  eth_get_headlen
	2.03%  mlx4_en_process_rx_cq
	1.69%  mlx4_en_xmit
	1.19%  ip_rcv_finish
	1.12%  __probe_kernel_read
	1.02%  ehci_hcd_cleanup

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Kernel Team <kernel-team@fb.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1454531308-2441898-1-git-send-email-kafai@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-09 11:08:58 +01:00
Shilpasri G Bhat
0306e481d4 cpufreq: powernv/tracing: Add powernv_throttle tracepoint
This patch adds the powernv_throttle tracepoint to trace the CPU
frequency throttling event, which is used by the powernv-cpufreq
driver in POWER8.

Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-05 02:38:02 +01:00
Linus Torvalds
ef582d095d A cleanup to the stack tracer broke stack tracing on s390.
Here's a simple fix to correct that issue.
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Merge tag 'trace-v4.5-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "A cleanup to the stack tracer broke stack tracing on s390.  Here's a
  simple fix to correct that issue"

* tag 'trace-v4.5-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/stacktrace: Show entire trace if passed in function not found
2016-02-03 09:31:34 -08:00
Linus Torvalds
29d14f0835 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
 "This is much bigger than typical fixes, but Peter found a category of
  races that spurred more fixes and more debugging enhancements.  Work
  started before the merge window, but got finished only now.

  Aside of that this contains the usual small fixes to perf and tools.
  Nothing particular exciting"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (43 commits)
  perf: Remove/simplify lockdep annotation
  perf: Synchronously clean up child events
  perf: Untangle 'owner' confusion
  perf: Add flags argument to perf_remove_from_context()
  perf: Clean up sync_child_event()
  perf: Robustify event->owner usage and SMP ordering
  perf: Fix STATE_EXIT usage
  perf: Update locking order
  perf: Remove __free_event()
  perf/bpf: Convert perf_event_array to use struct file
  perf: Fix NULL deref
  perf/x86: De-obfuscate code
  perf/x86: Fix uninitialized value usage
  perf: Fix race in perf_event_exit_task_context()
  perf: Fix orphan hole
  perf stat: Do not clean event's private stats
  perf hists: Fix HISTC_MEM_DCACHELINE width setting
  perf annotate browser: Fix behaviour of Shift-Tab with nothing focussed
  perf tests: Remove wrong semicolon in while loop in CQM test
  perf: Synchronously free aux pages in case of allocation failure
  ...
2016-01-31 15:38:27 -08:00
Steven Rostedt
6ccd83714a tracing/stacktrace: Show entire trace if passed in function not found
When a max stack trace is discovered, the stack dump is saved. In order to
not record the overhead of the stack tracer, the ip of the traced function
is looked for within the dump. The trace is started from the location of
that function. But if for some reason the ip is not found, the entire stack
trace is then truncated. That's not very useful. Instead, print everything
if the ip of the traced function is not found within the trace.

This issue showed up on s390.

Link: http://lkml.kernel.org/r/20160129102241.1b3c9c04@gandalf.local.home

Fixes: 72ac426a5b ("tracing: Clean up stack tracing and fix fentry updates")
Cc: stable@vger.kernel.org # v4.3+
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-01-29 12:19:10 -05:00
Alexei Starovoitov
e03e7ee34f perf/bpf: Convert perf_event_array to use struct file
Robustify refcounting.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: vince@deater.net
Link: http://lkml.kernel.org/r/20160126045947.GA40151@ast-mbp.thefacebook.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-29 08:35:25 +01:00
Linus Torvalds
26cd83670f This includes three minor fixes, mostly due to cut-and-paste issues.
The first is a cut and paste issue that changed the amount of stack
 to skip when tracing a stack dump from 0 to 6, which basically made
 the stack disappear for small stack traces.
 
 The second fix is just removing an unused field in a struct that is no
 longer used, and currently just wastes space.
 
 The third is another cut-and-paste fix that had a tracepoint recording
 the wrong field (it was recording the previous field a second time).
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Merge tag 'trace-v4.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull minor tracing fixes from Steven Rostedt:
 "This includes three minor fixes, mostly due to cut-and-paste issues.

  The first is a cut and paste issue that changed the amount of stack to
  skip when tracing a stack dump from 0 to 6, which basically made the
  stack disappear for small stack traces.

  The second fix is just removing an unused field in a struct that is no
  longer used, and currently just wastes space.

  The third is another cut-and-paste fix that had a tracepoint recording
  the wrong field (it was recording the previous field a second time)"

* tag 'trace-v4.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/dma-buf/fence: Fix timeline str value on fence_annotate_wait_on
  ftrace: Remove unused nr_trampolines var
  tracing: Fix stacktrace skip depth in trace_buffer_unlock_commit_regs()
2016-01-28 17:00:50 -08:00
Steven Rostedt (Red Hat)
7717c6be69 tracing: Fix stacktrace skip depth in trace_buffer_unlock_commit_regs()
While cleaning the stacktrace code I unintentially changed the skip depth of
trace_buffer_unlock_commit_regs() from 0 to 6. kprobes uses this function,
and with skipping 6 call backs, it can easily produce no stack.

Here's how I tested it:

 # echo 'p:ext4_sync_fs ext4_sync_fs ' > /sys/kernel/debug/tracing/kprobe_events
 # echo 1 > /sys/kernel/debug/tracing/events/kprobes/enable
 # cat /sys/kernel/debug/trace
            sync-2394  [005]   502.457060: ext4_sync_fs: (ffffffff81317650)
            sync-2394  [005]   502.457063: kernel_stack:         <stack trace>
            sync-2394  [005]   502.457086: ext4_sync_fs: (ffffffff81317650)
            sync-2394  [005]   502.457087: kernel_stack:         <stack trace>
            sync-2394  [005]   502.457091: ext4_sync_fs: (ffffffff81317650)

After putting back the skip stack to zero, we have:

            sync-2270  [000]   748.052693: ext4_sync_fs: (ffffffff81317650)
            sync-2270  [000]   748.052695: kernel_stack:         <stack trace>
 => iterate_supers (ffffffff8126412e)
 => sys_sync (ffffffff8129c4b6)
 => entry_SYSCALL_64_fastpath (ffffffff8181f0b2)
            sync-2270  [000]   748.053017: ext4_sync_fs: (ffffffff81317650)
            sync-2270  [000]   748.053019: kernel_stack:         <stack trace>
 => iterate_supers (ffffffff8126412e)
 => sys_sync (ffffffff8129c4b6)
 => entry_SYSCALL_64_fastpath (ffffffff8181f0b2)
            sync-2270  [000]   748.053381: ext4_sync_fs: (ffffffff81317650)
            sync-2270  [000]   748.053383: kernel_stack:         <stack trace>
 => iterate_supers (ffffffff8126412e)
 => sys_sync (ffffffff8129c4b6)
 => entry_SYSCALL_64_fastpath (ffffffff8181f0b2)

Cc: stable@vger.kernel.org # v4.4+
Fixes: 73dddbb57b "tracing: Only create stacktrace option when STACKTRACE is configured"
Reported-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-01-14 09:28:19 -05:00
Linus Torvalds
c17488d066 Not much new with tracing for this release. Mostly just clean ups and
minor fixes.
 
 Here's what else is new:
 
  o  A new TRACE_EVENT_FN_COND macro, combining both _FN and _COND for
     those that want both.
 
  o  New selftest to test the instance create and delete
 
  o  Better debug output when ftrace fails
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Merge tag 'trace-v4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "Not much new with tracing for this release.  Mostly just clean ups and
  minor fixes.

  Here's what else is new:

   - A new TRACE_EVENT_FN_COND macro, combining both _FN and _COND for
     those that want both.

   - New selftest to test the instance create and delete

   - Better debug output when ftrace fails"

* tag 'trace-v4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (24 commits)
  ftrace: Fix the race between ftrace and insmod
  ftrace: Add infrastructure for delayed enabling of module functions
  x86: ftrace: Fix the comments for ftrace_modify_code_direct()
  tracing: Fix comment to use tracing_on over tracing_enable
  metag: ftrace: Fix the comments for ftrace_modify_code
  sh: ftrace: Fix the comments for ftrace_modify_code()
  ia64: ftrace: Fix the comments for ftrace_modify_code()
  ftrace: Clean up ftrace_module_init() code
  ftrace: Join functions ftrace_module_init() and ftrace_init_module()
  tracing: Introduce TRACE_EVENT_FN_COND macro
  tracing: Use seq_buf_used() in seq_buf_to_user() instead of len
  bpf: Constify bpf_verifier_ops structure
  ftrace: Have ftrace_ops_get_func() handle RCU and PER_CPU flags too
  ftrace: Remove use of control list and ops
  ftrace: Fix output of enabled_functions for showing tramp
  ftrace: Fix a typo in comment
  ftrace: Show all tramps registered to a record on ftrace_bug()
  ftrace: Add variable ftrace_expected for archs to show expected code
  ftrace: Add new type to distinguish what kind of ftrace_bug()
  tracing: Update cond flag when enabling or disabling a trigger
  ...
2016-01-12 20:04:15 -08:00
Linus Torvalds
33caf82acf Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
 "All kinds of stuff.  That probably should've been 5 or 6 separate
  branches, but by the time I'd realized how large and mixed that bag
  had become it had been too close to -final to play with rebasing.

  Some fs/namei.c cleanups there, memdup_user_nul() introduction and
  switching open-coded instances, burying long-dead code, whack-a-mole
  of various kinds, several new helpers for ->llseek(), assorted
  cleanups and fixes from various people, etc.

  One piece probably deserves special mention - Neil's
  lookup_one_len_unlocked().  Similar to lookup_one_len(), but gets
  called without ->i_mutex and tries to avoid ever taking it.  That, of
  course, means that it's not useful for any directory modifications,
  but things like getting inode attributes in nfds readdirplus are fine
  with that.  I really should've asked for moratorium on lookup-related
  changes this cycle, but since I hadn't done that early enough...  I
  *am* asking for that for the coming cycle, though - I'm going to try
  and get conversion of i_mutex to rwsem with ->lookup() done under lock
  taken shared.

  There will be a patch closer to the end of the window, along the lines
  of the one Linus had posted last May - mechanical conversion of
  ->i_mutex accesses to inode_lock()/inode_unlock()/inode_trylock()/
  inode_is_locked()/inode_lock_nested().  To quote Linus back then:

    -----
    |    This is an automated patch using
    |
    |        sed 's/mutex_lock(&\(.*\)->i_mutex)/inode_lock(\1)/'
    |        sed 's/mutex_unlock(&\(.*\)->i_mutex)/inode_unlock(\1)/'
    |        sed 's/mutex_lock_nested(&\(.*\)->i_mutex,[     ]*I_MUTEX_\([A-Z0-9_]*\))/inode_lock_nested(\1, I_MUTEX_\2)/'
    |        sed 's/mutex_is_locked(&\(.*\)->i_mutex)/inode_is_locked(\1)/'
    |        sed 's/mutex_trylock(&\(.*\)->i_mutex)/inode_trylock(\1)/'
    |
    |    with a very few manual fixups
    -----

  I'm going to send that once the ->i_mutex-affecting stuff in -next
  gets mostly merged (or when Linus says he's about to stop taking
  merges)"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  nfsd: don't hold i_mutex over userspace upcalls
  fs:affs:Replace time_t with time64_t
  fs/9p: use fscache mutex rather than spinlock
  proc: add a reschedule point in proc_readfd_common()
  logfs: constify logfs_block_ops structures
  fcntl: allow to set O_DIRECT flag on pipe
  fs: __generic_file_splice_read retry lookup on AOP_TRUNCATED_PAGE
  fs: xattr: Use kvfree()
  [s390] page_to_phys() always returns a multiple of PAGE_SIZE
  nbd: use ->compat_ioctl()
  fs: use block_device name vsprintf helper
  lib/vsprintf: add %*pg format specifier
  fs: use gendisk->disk_name where possible
  poll: plug an unused argument to do_poll
  amdkfd: don't open-code memdup_user()
  cdrom: don't open-code memdup_user()
  rsxx: don't open-code memdup_user()
  mtip32xx: don't open-code memdup_user()
  [um] mconsole: don't open-code memdup_user_nul()
  [um] hostaudio: don't open-code memdup_user()
  ...
2016-01-12 17:11:47 -08:00
Qiu Peiyang
5156dca34a ftrace: Fix the race between ftrace and insmod
We hit ftrace_bug report when booting Android on a 64bit ATOM SOC chip.
Basically, there is a race between insmod and ftrace_run_update_code.

After load_module=>ftrace_module_init, another thread jumps in to call
ftrace_run_update_code=>ftrace_arch_code_modify_prepare
                        =>set_all_modules_text_rw, to change all modules
as RW. Since the new module is at MODULE_STATE_UNFORMED, the text attribute
is not changed. Then, the 2nd thread goes ahead to change codes.
However, load_module continues to call complete_formation=>set_section_ro_nx,
then 2nd thread would fail when probing the module's TEXT.

The patch fixes it by using notifier to delay the enabling of ftrace
records to the time when module is at state MODULE_STATE_COMING.

Link: http://lkml.kernel.org/r/567CE628.3000609@intel.com

Signed-off-by: Qiu Peiyang <peiyangx.qiu@intel.com>
Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-01-07 15:56:21 -05:00
Steven Rostedt (Red Hat)
b7ffffbb46 ftrace: Add infrastructure for delayed enabling of module functions
Qiu Peiyang pointed out that there's a race when enabling function tracing
and loading a module. In order to make the modifications of converting nops
in the prologue of functions into callbacks, the text needs to be converted
from read-only to read-write. When enabling function tracing, the text
permission is updated, the functions are modified, and then they are put
back.

When loading a module, the updates to convert function calls to mcount is
done before the module text is set to read-only. But after it is done, the
module text is visible by the function tracer. Thus we have the following
race:

	CPU 0			CPU 1
	-----			-----
   start function tracing
   set text to read-write
			     load_module
			     add functions to ftrace
			     set module text read-only

   update all functions to callbacks
   modify module functions too
   < Can't it's read-only >

When this happens, ftrace detects the issue and disables itself till the
next reboot.

To fix this, a new DISABLED flag is added for ftrace records, which all
module functions get when they are added. Then later, after the module code
is all set, the records will have the DISABLED flag cleared, and they will
be enabled if any callback wants all functions to be traced.

Note, this doesn't add the delay to later. It simply changes the
ftrace_module_init() to do both the setting of DISABLED records, and then
immediately calls the enable code. This helps with testing this new code as
it has the same behavior as previously. Another change will come after this
to have the ftrace_module_enable() called after the text is set to
read-only.

Cc: Qiu Peiyang <peiyangx.qiu@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-01-07 15:40:01 -05:00
Qiu Peiyang
f36d1be293 tracing: Fix setting of start_index in find_next()
When we do cat /sys/kernel/debug/tracing/printk_formats, we hit kernel
panic at t_show.

general protection fault: 0000 [#1] PREEMPT SMP
CPU: 0 PID: 2957 Comm: sh Tainted: G W  O 3.14.55-x86_64-01062-gd4acdc7 #2
RIP: 0010:[<ffffffff811375b2>]
 [<ffffffff811375b2>] t_show+0x22/0xe0
RSP: 0000:ffff88002b4ebe80  EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000004
RDX: 0000000000000004 RSI: ffffffff81fd26a6 RDI: ffff880032f9f7b1
RBP: ffff88002b4ebe98 R08: 0000000000001000 R09: 000000000000ffec
R10: 0000000000000000 R11: 000000000000000f R12: ffff880004d9b6c0
R13: 7365725f6d706400 R14: ffff880004d9b6c0 R15: ffffffff82020570
FS:  0000000000000000(0000) GS:ffff88003aa00000(0063) knlGS:00000000f776bc40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f6c02ff0 CR3: 000000002c2b3000 CR4: 00000000001007f0
Call Trace:
 [<ffffffff811dc076>] seq_read+0x2f6/0x3e0
 [<ffffffff811b749b>] vfs_read+0x9b/0x160
 [<ffffffff811b7f69>] SyS_read+0x49/0xb0
 [<ffffffff81a3a4b9>] ia32_do_call+0x13/0x13
 ---[ end trace 5bd9eb630614861e ]---
Kernel panic - not syncing: Fatal exception

When the first time find_next calls find_next_mod_format, it should
iterate the trace_bprintk_fmt_list to find the first print format of
the module. However in current code, start_index is smaller than *pos
at first, and code will not iterate the list. Latter container_of will
get the wrong address with former v, which will cause mod_fmt be a
meaningless object and so is the returned mod_fmt->fmt.

This patch will fix it by correcting the start_index. After fixed,
when the first time calls find_next_mod_format, start_index will be
equal to *pos, and code will iterate the trace_bprintk_fmt_list to
get the right module printk format, so is the returned mod_fmt->fmt.

Link: http://lkml.kernel.org/r/5684B900.9000309@intel.com

Cc: stable@vger.kernel.org # 3.12+
Fixes: 102c9323c3 "tracing: Add __tracepoint_string() to export string pointers"
Signed-off-by: Qiu Peiyang <peiyangx.qiu@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-01-04 15:22:47 -05:00
Al Viro
70f6cbb6f9 kernel/*: switch to memdup_user_nul()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-04 10:27:55 -05:00
Al Viro
16e5c1fc36 convert a bunch of open-coded instances of memdup_user_nul()
A _lot_ of ->write() instances were open-coding it; some are
converted to memdup_user_nul(), a lot more remain...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-04 10:26:58 -05:00
Chuyu Hu
05a724bd44 tracing: Fix comment to use tracing_on over tracing_enable
The file tracing_enable is obsolete and does not exist anymore. Replace
the comment that references it with the proper tracing_on file.

Link: http://lkml.kernel.org/r/1450787141-45544-1-git-send-email-chuhu@redhat.com

Signed-off-by: Chuyu Hu <chuhu@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-12-23 14:27:25 -05:00
Steven Rostedt (Red Hat)
97e9b4fca5 ftrace: Clean up ftrace_module_init() code
The start and end variables were only used when ftrace_module_init() was
split up into multiple functions. No need to keep them around after the
merger.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-12-23 14:27:23 -05:00
Abel Vesa
b6b71f66a1 ftrace: Join functions ftrace_module_init() and ftrace_init_module()
Simple cleanup. No need for two functions here.
The whole work can simply be done inside 'ftrace_module_init'.

Link: http://lkml.kernel.org/r/1449067197-5718-1-git-send-email-abelvesa@linux.com

Signed-off-by: Abel Vesa <abelvesa@linux.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-12-23 14:27:22 -05:00
Julia Lawall
27dff4e041 bpf: Constify bpf_verifier_ops structure
This bpf_verifier_ops structure is never modified, like the other
bpf_verifier_ops structures, so declare it as const.

Done with the help of Coccinelle.

Link: http://lkml.kernel.org/r/1449855359-13724-1-git-send-email-Julia.Lawall@lip6.fr

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-12-23 14:27:19 -05:00
Steven Rostedt (Red Hat)
c68c0fa293 ftrace: Have ftrace_ops_get_func() handle RCU and PER_CPU flags too
Jiri Olsa noted that the change to replace the control_ops did not update
the trampoline for when running perf on a single CPU and with CONFIG_PREEMPT
disabled (where dynamic ops, like perf, can use trampolines directly). The
result was that perf function could be called when RCU is not watching as
well as not handle the ftrace_local_disable().

Modify the ftrace_ops_get_func() to also check the RCU and PER_CPU ops flags
and use the recursive function if they are set. The recursive function is
modified to check those flags and execute the appropriate checks if they are
set.

Link: http://lkml.kernel.org/r/20151201134213.GA14155@krava.brq.redhat.com

Reported-by: Jiri Olsa <jolsa@redhat.com>
Patch-fixed-up-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-12-23 14:27:19 -05:00
Steven Rostedt (Red Hat)
ba27f2bc73 ftrace: Remove use of control list and ops
Currently perf has its own list function within the ftrace infrastructure
that seems to be used only to allow for it to have per-cpu disabling as well
as a check to make sure that it's not called while RCU is not watching. It
uses something called the "control_ops" which is used to iterate over ops
under it with the control_list_func().

The problem is that this control_ops and control_list_func unnecessarily
complicates the code. By replacing FTRACE_OPS_FL_CONTROL with two new flags
(FTRACE_OPS_FL_RCU and FTRACE_OPS_FL_PER_CPU) we can remove all the code
that is special with the control ops and add the needed checks within the
generic ftrace_list_func().

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-12-23 14:27:18 -05:00
Steven Rostedt (Red Hat)
030f4e1cb8 ftrace: Fix output of enabled_functions for showing tramp
When showing all tramps registered to a ftrace record in the file
enabled_functions, it exits the loop with ops == NULL. But then it is
suppose to show the function on the ops->trampoline and
add_trampoline_func() is called with the given ops. But because ops is now
NULL (to exit the loop), it always shows the static trampoline instead of
the one that is really registered to the record.

The call to add_trampoline_func() that shows the trampoline for the given
ops needs to be called at every iteration.

Fixes: 39daa7b9e8 "ftrace: Show all tramps registered to a record on ftrace_bug()"
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-12-23 14:27:17 -05:00
Li Bin
b8ec330a63 ftrace: Fix a typo in comment
s/ARCH_SUPPORT_FTARCE_OPS/ARCH_SUPPORTS_FTRACE_OPS/

Link: http://lkml.kernel.org/r/1448879016-8659-1-git-send-email-huawei.libin@huawei.com

Signed-off-by: Li Bin <huawei.libin@huawei.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-12-23 14:26:51 -05:00
Linus Torvalds
51825c8a86 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "This tree includes four core perf fixes for misc bugs, three fixes to
  x86 PMU drivers, and two updates to old email addresses"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Do not send exit event twice
  perf/x86/intel: Fix INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_NA macro
  perf/x86/intel: Make L1D_PEND_MISS.FB_FULL not constrained on Haswell
  perf: Fix PERF_EVENT_IOC_PERIOD deadlock
  treewide: Remove old email address
  perf/x86: Fix LBR call stack save/restore
  perf: Update email address in MAINTAINERS
  perf/core: Robustify the perf_cgroup_from_task() RCU checks
  perf/core: Fix RCU problem with cgroup context switching code
2015-12-08 13:01:23 -08:00
Steven Rostedt (Red Hat)
0f72e37e42 tracing: Add sched_wakeup_new and sched_waking tracepoints for pid filter
The set_event_pid filter relies on attaching to the sched_switch and
sched_wakeup tracepoints to see if it should filter the tracing on schedule
tracepoints. By adding the callbacks to sched_wakeup, pids in the
set_event_pid file will trace the wakeups of those tasks with those pids.

But sched_wakeup_new and sched_waking were missed. These two should also be
traced. Luckily, these tracepoints share the same class as sched_wakeup
which means they can use the same pre and post callbacks as sched_wakeup
does.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-12-01 16:08:05 -05:00